Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
[linux-2.6-block.git] / arch / s390 / Kconfig
CommitLineData
b2441318 1# SPDX-License-Identifier: GPL-2.0
1da177e4 2config MMU
61d48c2c 3 def_bool y
1da177e4 4
66701b14 5config ZONE_DMA
69dbb2f7 6 def_bool y
66701b14 7
2fd92273
HC
8config CPU_BIG_ENDIAN
9 def_bool y
10
2b105ff9 11config LOCKDEP_SUPPORT
61d48c2c 12 def_bool y
2b105ff9 13
5bdc9b44 14config STACKTRACE_SUPPORT
61d48c2c 15 def_bool y
5bdc9b44 16
1da177e4
LT
17config RWSEM_GENERIC_SPINLOCK
18 bool
19
20config RWSEM_XCHGADD_ALGORITHM
61d48c2c 21 def_bool y
1da177e4 22
f0d1b0b3 23config ARCH_HAS_ILOG2_U32
6f9a3c33 24 def_bool n
f0d1b0b3
DH
25
26config ARCH_HAS_ILOG2_U64
6f9a3c33 27 def_bool n
f0d1b0b3 28
7e33db4e 29config GENERIC_HWEIGHT
61d48c2c 30 def_bool y
7e33db4e 31
c0007f1a 32config GENERIC_BUG
6f9a3c33 33 def_bool y if BUG
c0007f1a 34
52499f40
HC
35config GENERIC_BUG_RELATIVE_POINTERS
36 def_bool y
37
b6b40c53 38config GENERIC_LOCKBREAK
6f9a3c33 39 def_bool y if SMP && PREEMPT
b6b40c53 40
402b0862 41config PGSTE
6f9a3c33 42 def_bool y if KVM
402b0862 43
6a11f75b
AM
44config ARCH_SUPPORTS_DEBUG_PAGEALLOC
45 def_bool y
46
843c48fd
JG
47config AUDIT_ARCH
48 def_bool y
49
ce816fa8 50config NO_IOPORT_MAP
c8717a3d
JG
51 def_bool y
52
53config PCI_QUIRKS
54 def_bool n
55
2a0a5b22 56config ARCH_SUPPORTS_UPROBES
5a79859a 57 def_bool y
2a0a5b22 58
347a8dc3 59config S390
61d48c2c 60 def_bool y
23fefe11 61 select ARCH_BINFMT_ELF_STATE
21266be9 62 select ARCH_HAS_DEVMEM_IS_ALLOWED
2b68f6ca 63 select ARCH_HAS_ELF_RANDOMIZE
79962038 64 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 65 select ARCH_HAS_GCOV_PROFILE_ALL
e1073d1e 66 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
907fa061 67 select ARCH_HAS_KCOV
3010a5ea 68 select ARCH_HAS_PTE_SPECIAL
d2852a22 69 select ARCH_HAS_SET_MEMORY
47523c98 70 select ARCH_HAS_SG_CHAIN
ad21fc4f
LA
71 select ARCH_HAS_STRICT_KERNEL_RWX
72 select ARCH_HAS_STRICT_MODULE_RWX
c42d8c7d 73 select ARCH_HAS_UBSAN_SANITIZE_ALL
0e0d04a8 74 select ARCH_HAVE_NMI_SAFE_CMPXCHG
6beb0009
TG
75 select ARCH_INLINE_READ_LOCK
76 select ARCH_INLINE_READ_LOCK_BH
77 select ARCH_INLINE_READ_LOCK_IRQ
78 select ARCH_INLINE_READ_LOCK_IRQSAVE
0e0d04a8 79 select ARCH_INLINE_READ_TRYLOCK
6beb0009
TG
80 select ARCH_INLINE_READ_UNLOCK
81 select ARCH_INLINE_READ_UNLOCK_BH
82 select ARCH_INLINE_READ_UNLOCK_IRQ
83 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE
0e0d04a8
HC
84 select ARCH_INLINE_SPIN_LOCK
85 select ARCH_INLINE_SPIN_LOCK_BH
86 select ARCH_INLINE_SPIN_LOCK_IRQ
87 select ARCH_INLINE_SPIN_LOCK_IRQSAVE
88 select ARCH_INLINE_SPIN_TRYLOCK
89 select ARCH_INLINE_SPIN_TRYLOCK_BH
90 select ARCH_INLINE_SPIN_UNLOCK
91 select ARCH_INLINE_SPIN_UNLOCK_BH
92 select ARCH_INLINE_SPIN_UNLOCK_IRQ
93 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE
6beb0009
TG
94 select ARCH_INLINE_WRITE_LOCK
95 select ARCH_INLINE_WRITE_LOCK_BH
96 select ARCH_INLINE_WRITE_LOCK_IRQ
97 select ARCH_INLINE_WRITE_LOCK_IRQSAVE
0e0d04a8 98 select ARCH_INLINE_WRITE_TRYLOCK
6beb0009
TG
99 select ARCH_INLINE_WRITE_UNLOCK
100 select ARCH_INLINE_WRITE_UNLOCK_BH
101 select ARCH_INLINE_WRITE_UNLOCK_IRQ
102 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE
0e0d04a8 103 select ARCH_SAVE_PAGE_KEYS if HIBERNATION
36e7fdaa 104 select ARCH_SUPPORTS_ATOMIC_RMW
a763bc8b 105 select ARCH_SUPPORTS_NUMA_BALANCING
295d8fa9 106 select ARCH_USE_BUILTIN_BSWAP
efc1d23b 107 select ARCH_USE_CMPXCHG_LOCKREF
3f6813b9 108 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
c42d8c7d 109 select ARCH_WANTS_UBSAN_NO_NULL
c1d7e01d 110 select ARCH_WANT_IPC_PARSE_VERSION
0e0d04a8
HC
111 select BUILDTIME_EXTABLE_SORT
112 select CLONE_BACKWARDS2
5d6a0163 113 select DYNAMIC_FTRACE if FUNCTION_TRACER
0e0d04a8 114 select GENERIC_CLOCKEVENTS
8f00b3e2 115 select GENERIC_CPU_AUTOPROBE
0e0d04a8 116 select GENERIC_CPU_DEVICES if !SMP
d424986f 117 select GENERIC_CPU_VULNERABILITIES
746479cd 118 select GENERIC_FIND_FIRST_BIT
e80e7813 119 select GENERIC_SMP_IDLE_THREAD
79c74ecb 120 select GENERIC_TIME_VSYSCALL
0e0d04a8 121 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
7a017721 122 select HAVE_ARCH_AUDITSYSCALL
5a79859a 123 select HAVE_ARCH_JUMP_LABEL
fff7fb0b 124 select CPU_NO_EFFICIENT_FFS if !HAVE_MARCH_Z9_109_FEATURES
c63cb468 125 select HAVE_ARCH_SECCOMP_FILTER
5614dd92 126 select HAVE_ARCH_SOFT_DIRTY
0e0d04a8 127 select HAVE_ARCH_TRACEHOOK
5a79859a 128 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
6077776b 129 select HAVE_EBPF_JIT if PACK_STACK && HAVE_MARCH_Z196_FEATURES
0e0d04a8
HC
130 select HAVE_CMPXCHG_DOUBLE
131 select HAVE_CMPXCHG_LOCAL
f50c0e63 132 select HAVE_COPY_THREAD_TLS
0e0d04a8 133 select HAVE_DEBUG_KMEMLEAK
e1231b0e 134 select HAVE_DMA_CONTIGUOUS
002e6745 135 select DMA_DIRECT_OPS
5a79859a
HC
136 select HAVE_DYNAMIC_FTRACE
137 select HAVE_DYNAMIC_FTRACE_WITH_REGS
9078a549 138 select HAVE_EFFICIENT_UNALIGNED_ACCESS
0e0d04a8 139 select HAVE_FTRACE_MCOUNT_RECORD
5a79859a
HC
140 select HAVE_FUNCTION_GRAPH_TRACER
141 select HAVE_FUNCTION_TRACER
03b8c7b6 142 select HAVE_FUTEX_CMPXCHG if FUTEX
dfd4c493 143 select HAVE_GCC_PLUGINS
0e0d04a8
HC
144 select HAVE_KERNEL_BZIP2
145 select HAVE_KERNEL_GZIP
8e2872ce 146 select HAVE_KERNEL_LZ4
0e0d04a8
HC
147 select HAVE_KERNEL_LZMA
148 select HAVE_KERNEL_LZO
149 select HAVE_KERNEL_XZ
150 select HAVE_KPROBES
151 select HAVE_KRETPROBES
5a79859a 152 select HAVE_KVM
21042d43 153 select HAVE_LIVEPATCH
c33eff60
HC
154 select HAVE_PERF_REGS
155 select HAVE_PERF_USER_STACK_DUMP
0e0d04a8
HC
156 select HAVE_MEMBLOCK
157 select HAVE_MEMBLOCK_NODE_MAP
50be6345 158 select HAVE_MEMBLOCK_PHYS_MAP
786d35d4 159 select HAVE_MOD_ARCH_SPECIFIC
0e0d04a8
HC
160 select HAVE_OPROFILE
161 select HAVE_PERF_EVENTS
162 select HAVE_REGS_AND_STACK_ACCESS_API
163 select HAVE_SYSCALL_TRACEPOINTS
0e0d04a8 164 select HAVE_VIRT_CPU_ACCOUNTING
786d35d4 165 select MODULES_USE_ELF_RELA
50be6345 166 select NO_BOOTMEM
7eddd99c 167 select OLD_SIGACTION
93bead43 168 select OLD_SIGSUSPEND3
bb98f396 169 select SPARSE_IRQ
0e0d04a8 170 select SYSCTL_EXCEPTION_TRACE
d5c352cd 171 select THREAD_INFO_IN_TASK
0563416b 172 select TTY
0e0d04a8 173 select VIRT_CPU_ACCOUNTING
40565b5a 174 select ARCH_HAS_SCALED_CPUTIME
93bead43 175 select VIRT_TO_BUS
42a0bb3f 176 select HAVE_NMI
3a368f74 177
1da177e4 178
fca3e357 179config SCHED_OMIT_FRAME_POINTER
6f9a3c33 180 def_bool y
fca3e357 181
c81956c9
KS
182config PGTABLE_LEVELS
183 int
1aea9b3f 184 default 5
c81956c9 185
1da177e4
LT
186source "init/Kconfig"
187
dc52ddc0
MH
188source "kernel/Kconfig.freezer"
189
21042d43
JS
190source "kernel/livepatch/Kconfig"
191
843c48fd
JG
192menu "Processor type and features"
193
194config HAVE_MARCH_Z900_FEATURES
195 def_bool n
196
197config HAVE_MARCH_Z990_FEATURES
198 def_bool n
199 select HAVE_MARCH_Z900_FEATURES
200
201config HAVE_MARCH_Z9_109_FEATURES
202 def_bool n
203 select HAVE_MARCH_Z990_FEATURES
204
205config HAVE_MARCH_Z10_FEATURES
206 def_bool n
207 select HAVE_MARCH_Z9_109_FEATURES
208
209config HAVE_MARCH_Z196_FEATURES
210 def_bool n
211 select HAVE_MARCH_Z10_FEATURES
212
991c1505
HC
213config HAVE_MARCH_ZEC12_FEATURES
214 def_bool n
215 select HAVE_MARCH_Z196_FEATURES
216
f8b2dcbd
MS
217config HAVE_MARCH_Z13_FEATURES
218 def_bool n
219 select HAVE_MARCH_ZEC12_FEATURES
220
6997c323
MS
221config HAVE_MARCH_Z14_FEATURES
222 def_bool n
223 select HAVE_MARCH_Z13_FEATURES
224
843c48fd
JG
225choice
226 prompt "Processor type"
7072276e 227 default MARCH_Z196
1da177e4 228
843c48fd
JG
229config MARCH_Z900
230 bool "IBM zSeries model z800 and z900"
5a79859a 231 select HAVE_MARCH_Z900_FEATURES
843c48fd
JG
232 help
233 Select this to enable optimizations for model z800/z900 (2064 and
234 2066 series). This will enable some optimizations that are not
235 available on older ESA/390 (31 Bit) only CPUs.
236
237config MARCH_Z990
238 bool "IBM zSeries model z890 and z990"
5a79859a 239 select HAVE_MARCH_Z990_FEATURES
843c48fd
JG
240 help
241 Select this to enable optimizations for model z890/z990 (2084 and
242 2086 series). The kernel will be slightly faster but will not work
243 on older machines.
244
245config MARCH_Z9_109
246 bool "IBM System z9"
5a79859a 247 select HAVE_MARCH_Z9_109_FEATURES
843c48fd
JG
248 help
249 Select this to enable optimizations for IBM System z9 (2094 and
250 2096 series). The kernel will be slightly faster but will not work
251 on older machines.
252
253config MARCH_Z10
254 bool "IBM System z10"
5a79859a 255 select HAVE_MARCH_Z10_FEATURES
843c48fd
JG
256 help
257 Select this to enable optimizations for IBM System z10 (2097 and
258 2098 series). The kernel will be slightly faster but will not work
259 on older machines.
260
261config MARCH_Z196
262 bool "IBM zEnterprise 114 and 196"
5a79859a 263 select HAVE_MARCH_Z196_FEATURES
843c48fd
JG
264 help
265 Select this to enable optimizations for IBM zEnterprise 114 and 196
266 (2818 and 2817 series). The kernel will be slightly faster but will
267 not work on older machines.
1da177e4 268
991c1505 269config MARCH_ZEC12
59471227 270 bool "IBM zBC12 and zEC12"
5a79859a 271 select HAVE_MARCH_ZEC12_FEATURES
991c1505 272 help
59471227
HC
273 Select this to enable optimizations for IBM zBC12 and zEC12 (2828 and
274 2827 series). The kernel will be slightly faster but will not work on
275 older machines.
991c1505 276
f8b2dcbd 277config MARCH_Z13
bb3aa614 278 bool "IBM z13s and z13"
5a79859a 279 select HAVE_MARCH_Z13_FEATURES
f8b2dcbd 280 help
bb3aa614
HC
281 Select this to enable optimizations for IBM z13s and z13 (2965 and
282 2964 series). The kernel will be slightly faster but will not work on
283 older machines.
f8b2dcbd 284
6997c323 285config MARCH_Z14
451239eb 286 bool "IBM z14 ZR1 and z14"
6997c323
MS
287 select HAVE_MARCH_Z14_FEATURES
288 help
451239eb
HC
289 Select this to enable optimizations for IBM z14 ZR1 and z14 (3907
290 and 3906 series). The kernel will be slightly faster but will not
291 work on older machines.
6997c323 292
843c48fd 293endchoice
1da177e4 294
1db9e051
HC
295config MARCH_Z900_TUNE
296 def_bool TUNE_Z900 || MARCH_Z900 && TUNE_DEFAULT
297
298config MARCH_Z990_TUNE
299 def_bool TUNE_Z990 || MARCH_Z990 && TUNE_DEFAULT
300
301config MARCH_Z9_109_TUNE
302 def_bool TUNE_Z9_109 || MARCH_Z9_109 && TUNE_DEFAULT
303
304config MARCH_Z10_TUNE
305 def_bool TUNE_Z10 || MARCH_Z10 && TUNE_DEFAULT
306
307config MARCH_Z196_TUNE
308 def_bool TUNE_Z196 || MARCH_Z196 && TUNE_DEFAULT
309
310config MARCH_ZEC12_TUNE
311 def_bool TUNE_ZEC12 || MARCH_ZEC12 && TUNE_DEFAULT
312
f8b2dcbd
MS
313config MARCH_Z13_TUNE
314 def_bool TUNE_Z13 || MARCH_Z13 && TUNE_DEFAULT
315
6997c323
MS
316config MARCH_Z14_TUNE
317 def_bool TUNE_Z14 || MARCH_Z14 && TUNE_DEFAULT
318
1db9e051
HC
319choice
320 prompt "Tune code generation"
321 default TUNE_DEFAULT
322 help
323 Cause the compiler to tune (-mtune) the generated code for a machine.
324 This will make the code run faster on the selected machine but
325 somewhat slower on other machines.
326 This option only changes how the compiler emits instructions, not the
327 selection of instructions itself, so the resulting kernel will run on
328 all other machines.
329
330config TUNE_DEFAULT
331 bool "Default"
332 help
333 Tune the generated code for the target processor for which the kernel
334 will be compiled.
335
1db9e051
HC
336config TUNE_Z900
337 bool "IBM zSeries model z800 and z900"
338
339config TUNE_Z990
340 bool "IBM zSeries model z890 and z990"
341
342config TUNE_Z9_109
343 bool "IBM System z9"
344
345config TUNE_Z10
346 bool "IBM System z10"
347
348config TUNE_Z196
349 bool "IBM zEnterprise 114 and 196"
350
351config TUNE_ZEC12
352 bool "IBM zBC12 and zEC12"
353
f8b2dcbd
MS
354config TUNE_Z13
355 bool "IBM z13"
356
6997c323
MS
357config TUNE_Z14
358 bool "IBM z14"
359
1db9e051
HC
360endchoice
361
347a8dc3 362config 64BIT
6f9a3c33 363 def_bool y
d9f7a745 364
843c48fd
JG
365config COMPAT
366 def_bool y
367 prompt "Kernel support for 31 bit emulation"
843c48fd
JG
368 select COMPAT_BINFMT_ELF if BINFMT_ELF
369 select ARCH_WANT_OLD_COMPAT_IPC
7eddd99c 370 select COMPAT_OLD_SIGACTION
2813893f 371 depends on MULTIUSER
843c48fd
JG
372 help
373 Select this option if you want to enable your system kernel to
374 handle system-calls from ELF binaries for 31 bit ESA. This option
375 (and some other stuff like libraries and such) is needed for
376 executing 31 bit applications. It is safe to say "Y".
377
378config SYSVIPC_COMPAT
379 def_bool y if COMPAT && SYSVIPC
380
1da177e4 381config SMP
6f9a3c33
MS
382 def_bool y
383 prompt "Symmetric multi-processing support"
1da177e4
LT
384 ---help---
385 This enables support for systems with more than one CPU. If you have
386 a system with only one CPU, like most personal computers, say N. If
387 you have a system with more than one CPU, say Y.
388
4a474157 389 If you say N here, the kernel will run on uni- and multiprocessor
1da177e4
LT
390 machines, but will use only one CPU of a multiprocessor machine. If
391 you say Y here, the kernel will run on many, but not all,
4a474157 392 uniprocessor machines. On a uniprocessor machine, the kernel
1da177e4
LT
393 will run faster if you say N here.
394
03502faa
AB
395 See also the SMP-HOWTO available at
396 <http://www.tldp.org/docs.html#howto>.
1da177e4
LT
397
398 Even if you don't know what to do here, say Y.
399
400config NR_CPUS
5c75a0da
HC
401 int "Maximum number of CPUs (2-512)"
402 range 2 512
1da177e4 403 depends on SMP
5a79859a 404 default "64"
1da177e4
LT
405 help
406 This allows you to specify the maximum number of CPUs which this
5c75a0da 407 kernel will support. The maximum supported value is 512 and the
1da177e4
LT
408 minimum value which makes sense is 2.
409
410 This is purely to save memory - each supported CPU adds
411 approximately sixteen kilobytes to the kernel image.
412
413config HOTPLUG_CPU
6f9a3c33
MS
414 def_bool y
415 prompt "Support for hot-pluggable CPUs"
1da177e4 416 depends on SMP
1da177e4
LT
417 help
418 Say Y here to be able to turn CPUs off and on. CPUs
419 can be controlled through /sys/devices/system/cpu/cpu#.
420 Say N if you want to disable CPU hotplug.
421
3a368f74
PH
422# Some NUMA nodes have memory ranges that span
423# other nodes. Even though a pfn is valid and
424# between a node's start and end pfns, it may not
425# reside on that node. See memmap_init_zone()
426# for details. <- They meant memory holes!
427config NODES_SPAN_OTHER_NODES
428 def_bool NUMA
429
430config NUMA
431 bool "NUMA support"
c095a949 432 depends on SMP && SCHED_TOPOLOGY
3a368f74
PH
433 default n
434 help
435 Enable NUMA support
436
437 This option adds NUMA support to the kernel.
438
439 An operation mode can be selected by appending
440 numa=<method> to the kernel command line.
441
442 The default behaviour is identical to appending numa=plain to
443 the command line. This will create just one node with all
444 available memory and all CPUs in it.
445
446config NODES_SHIFT
447 int "Maximum NUMA nodes (as a power of 2)"
448 range 1 10
449 depends on NUMA
450 default "4"
451 help
452 Specify the maximum number of NUMA nodes available on the target
453 system. Increases memory reserved to accommodate various tables.
454
c29a7baf
MH
455menu "Select NUMA modes"
456 depends on NUMA
457
458config NUMA_EMU
459 bool "NUMA emulation"
460 default y
461 help
462 Numa emulation mode will split the available system memory into
463 equal chunks which then are distributed over the configured number
464 of nodes in a round-robin manner.
465
466 The number of fake nodes is limited by the number of available memory
467 chunks (i.e. memory size / fake size) and the number of supported
468 nodes in the kernel.
469
470 The CPUs are assigned to the nodes in a way that partially respects
471 the original machine topology (if supported by the machine).
472 Fair distribution of the CPUs is not guaranteed.
473
474config EMU_SIZE
475 hex "NUMA emulation memory chunk size"
476 default 0x10000000
477 range 0x400000 0x100000000
478 depends on NUMA_EMU
479 help
480 Select the default size by which the memory is chopped and then
481 assigned to emulated NUMA nodes.
482
483 This can be overridden by specifying
484
485 emu_size=<n>
486
487 on the kernel command line where also suffixes K, M, G, and T are
488 supported.
489
490endmenu
9236b4dd
HC
491
492config SCHED_SMT
493 def_bool n
c29a7baf 494
8d11e021 495config SCHED_MC
83a24e32 496 def_bool n
8d11e021 497
4cb14bc8 498config SCHED_BOOK
10ad34bc
MS
499 def_bool n
500
adac0f1e
HC
501config SCHED_DRAWER
502 def_bool n
503
10ad34bc 504config SCHED_TOPOLOGY
6f9a3c33 505 def_bool y
10ad34bc 506 prompt "Topology scheduler support"
83a24e32 507 depends on SMP
10ad34bc 508 select SCHED_SMT
83a24e32 509 select SCHED_MC
10ad34bc 510 select SCHED_BOOK
adac0f1e 511 select SCHED_DRAWER
4cb14bc8 512 help
10ad34bc
MS
513 Topology scheduler support improves the CPU scheduler's decision
514 making when dealing with machines that have multi-threading,
515 multiple cores or multiple books.
4cb14bc8 516
843c48fd
JG
517source kernel/Kconfig.preempt
518
843c48fd 519source kernel/Kconfig.hz
1da177e4 520
bdea9f6f
PR
521config KEXEC
522 def_bool y
523 select KEXEC_CORE
524
525config KEXEC_FILE
526 bool "kexec file based system call"
527 select KEXEC_CORE
528 select BUILD_BIN2C
529 depends on CRYPTO
530 depends on CRYPTO_SHA256
531 depends on CRYPTO_SHA256_S390
532 help
533 Enable the kexec file based system call. In contrast to the normal
534 kexec system call this system call takes file descriptors for the
535 kernel and initramfs as arguments.
536
537config ARCH_HAS_KEXEC_PURGATORY
538 def_bool y
539 depends on KEXEC_FILE
540
4c637cd8
HF
541config ARCH_RANDOM
542 def_bool y
543 prompt "s390 architectural random number generation API"
544 help
545 Enable the s390 architectural random number generation API
546 to provide random data for all consumers within the Linux
547 kernel.
548
549 When enabled the arch_random_* functions declared in linux/random.h
550 are implemented. The implementation is based on the s390 CPACF
551 instruction subfunction TRNG which provides a real true random
552 number generator.
553
554 If unsure, say Y.
555
d768bd89
MS
556config KERNEL_NOBP
557 def_bool n
558 prompt "Enable modified branch prediction for the kernel by default"
559 help
560 If this option is selected the kernel will switch to a modified
561 branch prediction mode if the firmware interface is available.
562 The modified branch prediction mode improves the behaviour in
563 regard to speculative execution.
564
565 With the option enabled the kernel parameter "nobp=0" or "nospec"
566 can be used to run the kernel in the normal branch prediction mode.
567
568 With the option disabled the modified branch prediction mode is
569 enabled with the "nobp=1" kernel parameter.
570
571 If unsure, say N.
572
f19fbd5e
MS
573config EXPOLINE
574 def_bool n
575 prompt "Avoid speculative indirect branches in the kernel"
576 help
577 Compile the kernel with the expoline compiler options to guard
578 against kernel-to-user data leaks by avoiding speculative indirect
579 branches.
580 Requires a compiler with -mindirect-branch=thunk support for full
581 protection. The kernel may run slower.
582
583 If unsure, say N.
584
585choice
586 prompt "Expoline default"
587 depends on EXPOLINE
588 default EXPOLINE_FULL
589
590config EXPOLINE_OFF
591 bool "spectre_v2=off"
592
6e179d64 593config EXPOLINE_AUTO
f19fbd5e
MS
594 bool "spectre_v2=auto"
595
596config EXPOLINE_FULL
597 bool "spectre_v2=on"
598
599endchoice
600
843c48fd 601endmenu
1da177e4 602
843c48fd 603menu "Memory setup"
1d057720 604
843c48fd 605config ARCH_SPARSEMEM_ENABLE
6f9a3c33 606 def_bool y
843c48fd
JG
607 select SPARSEMEM_VMEMMAP_ENABLE
608 select SPARSEMEM_VMEMMAP
e65e1fc2 609
843c48fd
JG
610config ARCH_SPARSEMEM_DEFAULT
611 def_bool y
1da177e4 612
843c48fd
JG
613config ARCH_SELECT_MEMORY_MODEL
614 def_bool y
1da177e4 615
843c48fd
JG
616config ARCH_ENABLE_MEMORY_HOTPLUG
617 def_bool y if SPARSEMEM
0efa4703 618
843c48fd
JG
619config ARCH_ENABLE_MEMORY_HOTREMOVE
620 def_bool y
e37f50e1 621
ec66ad66
MS
622config ARCH_ENABLE_SPLIT_PMD_PTLOCK
623 def_bool y
ec66ad66 624
843c48fd
JG
625config FORCE_MAX_ZONEORDER
626 int
627 default "9"
f861e405 628
843c48fd 629source "mm/Kconfig"
1da177e4 630
b8402b95
HC
631config MAX_PHYSMEM_BITS
632 int "Maximum size of supported physical memory in bits (42-53)"
633 range 42 53
634 default "46"
635 help
636 This option specifies the maximum supported size of physical memory
637 in bits. Supported is any size between 2^42 (4TB) and 2^53 (8PB).
638 Increasing the number of bits also increases the kernel image size.
639 By default 46 bits (64TB) are supported.
640
1da177e4 641config PACK_STACK
6f9a3c33
MS
642 def_bool y
643 prompt "Pack kernel stack"
1da177e4
LT
644 help
645 This option enables the compiler option -mkernel-backchain if it
646 is available. If the option is available the compiler supports
647 the new stack layout which dramatically reduces the minimum stack
648 frame size. With an old compiler a non-leaf function needs a
649 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
650 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
651 and 24 byte on 64 bit.
652
653 Say Y if you are unsure.
654
1da177e4 655config CHECK_STACK
6f9a3c33
MS
656 def_bool y
657 prompt "Detect kernel stack overflow"
1da177e4
LT
658 help
659 This option enables the compiler option -mstack-guard and
660 -mstack-size if they are available. If the compiler supports them
661 it will emit additional code to each function prolog to trigger
662 an illegal operation if the kernel stack is about to overflow.
663
664 Say N if you are unsure.
665
666config STACK_GUARD
667 int "Size of the guard area (128-1024)"
668 range 128 1024
669 depends on CHECK_STACK
670 default "256"
671 help
672 This allows you to specify the size of the guard area at the lower
673 end of the kernel stack. If the kernel stack points into the guard
674 area on function entry an illegal operation is triggered. The size
675 needs to be a power of 2. Please keep in mind that the size of an
676 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
677 The minimum size for the stack guard should be 256 for 31 bit and
678 512 for 64 bit.
679
2c190da4 680config WARN_DYNAMIC_STACK
6f9a3c33 681 def_bool n
2c190da4 682 prompt "Emit compiler warnings for function with dynamic stack usage"
1da177e4 683 help
2c190da4
JG
684 This option enables the compiler option -mwarn-dynamicstack. If the
685 compiler supports this options generates warnings for functions
686 that dynamically allocate stack space using alloca.
1da177e4
LT
687
688 Say N if you are unsure.
689
843c48fd 690endmenu
3f22ab27 691
843c48fd 692menu "I/O subsystem"
1da177e4 693
1da177e4 694config QDIO
6f9a3c33
MS
695 def_tristate y
696 prompt "QDIO support"
1da177e4 697 ---help---
8129ee16 698 This driver provides the Queued Direct I/O base support for
efca13bc 699 IBM System z.
1da177e4
LT
700
701 To compile this driver as a module, choose M here: the
702 module will be called qdio.
703
704 If unsure, say Y.
705
c8717a3d
JG
706menuconfig PCI
707 bool "PCI support"
c8717a3d 708 select PCI_MSI
a4ce5a48 709 select IOMMU_HELPER
8128f23c 710 select IOMMU_SUPPORT
f616ab59 711 select NEED_DMA_MAP_STATE
86596f0a 712 select NEED_SG_DMA_LENGTH
a4ce5a48 713
c8717a3d
JG
714 help
715 Enable PCI support.
716
717if PCI
718
719config PCI_NR_FUNCTIONS
720 int "Maximum number of PCI functions (1-4096)"
721 range 1 4096
b18601b0 722 default "128"
c8717a3d
JG
723 help
724 This allows you to specify the maximum number of PCI functions which
725 this kernel will support.
726
727source "drivers/pci/Kconfig"
c8717a3d
JG
728
729endif # PCI
730
731config PCI_DOMAINS
732 def_bool PCI
733
734config HAS_IOMEM
735 def_bool PCI
736
9d92a7e1 737config CHSC_SCH
d9c11b1e 738 def_tristate m
6f9a3c33 739 prompt "Support for CHSC subchannels"
9d92a7e1
CH
740 help
741 This driver allows usage of CHSC subchannels. A CHSC subchannel
742 is usually present on LPAR only.
743 The driver creates a device /dev/chsc, which may be used to
744 obtain I/O configuration information about the machine and
745 to issue asynchronous chsc commands (DANGEROUS).
746 You will usually only want to use this interface on a special
747 LPAR designated for system management.
748
749 To compile this driver as a module, choose M here: the
750 module will be called chsc_sch.
751
752 If unsure, say N.
753
1d1c8f78
SO
754config SCM_BUS
755 def_bool y
1d1c8f78
SO
756 prompt "SCM bus driver"
757 help
758 Bus driver for Storage Class Memory.
759
eadb86ab
SO
760config EADM_SCH
761 def_tristate m
762 prompt "Support for EADM subchannels"
763 depends on SCM_BUS
764 help
765 This driver allows usage of EADM subchannels. EADM subchannels act
766 as a communication vehicle for SCM increments.
767
768 To compile this driver as a module, choose M here: the
769 module will be called eadm_sch.
770
63f1934d
DJS
771config VFIO_CCW
772 def_tristate n
773 prompt "Support for VFIO-CCW subchannels"
84cd8fc4 774 depends on S390_CCW_IOMMU && VFIO_MDEV
63f1934d
DJS
775 help
776 This driver allows usage of I/O subchannels via VFIO-CCW.
777
778 To compile this driver as a module, choose M here: the
779 module will be called vfio_ccw.
780
843c48fd
JG
781endmenu
782
783menu "Dump support"
784
785config CRASH_DUMP
786 bool "kernel crash dumps"
5a79859a 787 depends on SMP
843c48fd
JG
788 select KEXEC
789 help
790 Generate crash dump after being started by kexec.
791 Crash dump kernels are loaded in the main kernel with kexec-tools
792 into a specially reserved region and then later executed after
793 a crash by kdump/kexec.
843c48fd 794 Refer to <file:Documentation/s390/zfcpdump.txt> for more details on this.
bf28a597
MH
795 This option also enables s390 zfcpdump.
796 See also <file:Documentation/s390/zfcpdump.txt>
843c48fd
JG
797
798endmenu
799
800menu "Executable file formats / Emulations"
1da177e4 801
1da177e4
LT
802source "fs/Kconfig.binfmt"
803
843c48fd
JG
804config SECCOMP
805 def_bool y
806 prompt "Enable seccomp to safely compute untrusted bytecode"
807 depends on PROC_FS
808 help
809 This kernel feature is useful for number crunching applications
810 that may need to compute untrusted bytecode during their
811 execution. By using pipes or other transports made available to
812 the process as file descriptors supporting the read/write
813 syscalls, it's possible to isolate those applications in
814 their own address space using seccomp. Once seccomp is
815 enabled via /proc/<pid>/seccomp, it cannot be disabled
816 and the task is only allowed to execute a few safe syscalls
817 defined by each seccomp mode.
818
819 If unsure, say Y.
820
821endmenu
822
823menu "Power Management"
824
825config ARCH_HIBERNATION_POSSIBLE
5a79859a 826 def_bool y
843c48fd
JG
827
828source "kernel/power/Kconfig"
829
830endmenu
831
832source "net/Kconfig"
833
834config PCMCIA
835 def_bool n
836
837config CCW
838 def_bool y
839
840source "drivers/Kconfig"
841
b6ef86e9
UB
842config HAVE_PNETID
843 tristate
844 default (SMC || CCWGROUP)
845
843c48fd
JG
846source "fs/Kconfig"
847
848source "arch/s390/Kconfig.debug"
849
850source "security/Kconfig"
851
852source "crypto/Kconfig"
853
854source "lib/Kconfig"
855
856menu "Virtualization"
684de39b 857
1da177e4 858config PFAULT
6f9a3c33
MS
859 def_bool y
860 prompt "Pseudo page fault support"
1da177e4
LT
861 help
862 Select this option, if you want to use PFAULT pseudo page fault
863 handling under VM. If running native or in LPAR, this option
864 has no effect. If your VM does not support PFAULT, PAGEEX
865 pseudo page fault handling will be used.
866 Note that VM 4.2 supports PFAULT but has a bug in its
867 implementation that causes some problems.
868 Everybody who wants to run Linux under VM != VM4.2 should select
869 this option.
870
1da177e4 871config CMM
6f9a3c33
MS
872 def_tristate n
873 prompt "Cooperative memory management"
1da177e4
LT
874 help
875 Select this option, if you want to enable the kernel interface
876 to reduce the memory size of the system. This is accomplished
877 by allocating pages of memory and put them "on hold". This only
878 makes sense for a system running under VM where the unused pages
879 will be reused by VM for other guest systems. The interface
880 allows an external monitor to balance memory of many systems.
881 Everybody who wants to run Linux under VM should select this
882 option.
883
1da177e4 884config CMM_IUCV
6f9a3c33
MS
885 def_bool y
886 prompt "IUCV special message interface to cooperative memory management"
1da177e4
LT
887 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
888 help
889 Select this option to enable the special message interface to
890 the cooperative memory management.
891
1da177e4 892config APPLDATA_BASE
6f9a3c33
MS
893 def_bool n
894 prompt "Linux - VM Monitor Stream, base infrastructure"
c185b783 895 depends on PROC_FS
1da177e4
LT
896 help
897 This provides a kernel interface for creating and updating z/VM APPLDATA
898 monitor records. The monitor records are updated at certain time
899 intervals, once the timer is started.
900 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
901 i.e. enables or disables monitoring on the Linux side.
902 A custom interval value (in seconds) can be written to
903 /proc/appldata/interval.
904
905 Defaults are 60 seconds interval and timer off.
906 The /proc entries can also be read from, showing the current settings.
907
908config APPLDATA_MEM
6f9a3c33
MS
909 def_tristate m
910 prompt "Monitor memory management statistics"
62fb2ba3 911 depends on APPLDATA_BASE && VM_EVENT_COUNTERS
1da177e4
LT
912 help
913 This provides memory management related data to the Linux - VM Monitor
914 Stream, like paging/swapping rate, memory utilisation, etc.
915 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
916 APPLDATA monitor record, i.e. enables or disables monitoring this record
917 on the z/VM side.
918
919 Default is disabled.
920 The /proc entry can also be read from, showing the current settings.
921
922 This can also be compiled as a module, which will be called
923 appldata_mem.o.
924
925config APPLDATA_OS
6f9a3c33
MS
926 def_tristate m
927 prompt "Monitor OS statistics"
1da177e4
LT
928 depends on APPLDATA_BASE
929 help
930 This provides OS related data to the Linux - VM Monitor Stream, like
931 CPU utilisation, etc.
932 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
933 APPLDATA monitor record, i.e. enables or disables monitoring this record
934 on the z/VM side.
935
936 Default is disabled.
937 This can also be compiled as a module, which will be called
938 appldata_os.o.
939
940config APPLDATA_NET_SUM
6f9a3c33
MS
941 def_tristate m
942 prompt "Monitor overall network statistics"
70193af9 943 depends on APPLDATA_BASE && NET
1da177e4
LT
944 help
945 This provides network related data to the Linux - VM Monitor Stream,
946 currently there is only a total sum of network I/O statistics, no
947 per-interface data.
948 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
949 APPLDATA monitor record, i.e. enables or disables monitoring this record
950 on the z/VM side.
951
952 Default is disabled.
953 This can also be compiled as a module, which will be called
954 appldata_net_sum.o.
955
24bbb1fa 956config S390_HYPFS_FS
6f9a3c33
MS
957 def_bool y
958 prompt "s390 hypervisor file system support"
24bbb1fa 959 select SYS_HYPERVISOR
24bbb1fa
MH
960 help
961 This is a virtual file system intended to provide accounting
962 information in an s390 hypervisor environment.
963
843c48fd 964source "arch/s390/kvm/Kconfig"
411ed322 965
fa587743 966config S390_GUEST
6f9a3c33 967 def_bool y
510cf5a6 968 prompt "s390 support for virtio devices"
79b6f7fb 969 select TTY
80629b0b 970 select VIRTUALIZATION
fa587743 971 select VIRTIO
faeba830 972 select VIRTIO_CONSOLE
fa587743 973 help
bdd1fc27
CH
974 Enabling this option adds support for virtio based paravirtual device
975 drivers on s390.
1da177e4 976
20766c08 977 Select this option if you want to run the kernel as a guest under
bdd1fc27 978 the KVM hypervisor.
155af2f9
HJP
979
980endmenu